22.2793GPPCombined Circuit Switched (CS) and IP Multimedia Subsystem (IMS) sessionsStage 1TS
For combinational services, it must be possible to charge as follows:
It shall be possible to provide charging information on the CS call and IMS session for correlation purposes in order to allow off-line charging.
The charging information shall continue to be produced for any remaining multimedia components or the CS call when a multimedia component or the CS call drops during the communication between the two parties.
Note: The below requirement will presumably not be feasible within Rel-7 timeframe, but may be considered in Rel-8.
The home operator should be able to correlate charged media components and CS call in order to introduce dedicated charging schemes, e.g. discounts. This applies to on-line charging as well as off-line charging.